Heres a good one...

As some of you may know I have a Toshiba laptop with XP and Vista on it, today I connected both XP and Vista to the domain at work.
Everything worked fine, I then disconnected XP from the domain, all was well.
Did the same with Vista and it now thinks my account is a guest account and when I try to do anything it wants an Administrator password but theres nowhere to put said admin password in but as its my password and it thinks I'm a guest, how would that work...

Nice one that